Identification of Block-oriented Systems with Rate Saturation Nonlinearity

System Identification in the Presence of a Saturation Nonlinearity

The paper deals with the identification of linear systems when they are in a pathway in series with a saturation nonlinearity. The objective is to estimate the parameters of the linear system and to obtain some characterisation of the nonlinearity, using only the input and output signals of the pathway. Both Wiener structures and Hammerstein structures are considered, and it is found that pertu...

Nonparametric Approach to Identification of Block-oriented Systems

An alternative philosophy of stochastic nonlinear system modelling is presented. We analyse the problem of the static nonlinearity, and the linear dynamics estimation in complex systems, under conditions of poor a priori knowledge. The parametric description of the other component and correlation structure of signals are assumed to be completely unknown. Two kinds of nonparametric methods (kern...

Identification of Block –oriented Models

Nonparametric instrumental variables for identification of block-oriented systems

A combined, parametric-nonparametric identification algorithm for a special case of NARMAX systems is proposed. The parameters of individual blocks are aggregated in one matrix (including mixed products of parameters). The matrix is estimated by an instrumental variables technique with the instruments generated by a nonparametric kernel method. Finally, the result is decomposed to obtain parame...

-Gain of Double Integrators With Saturation Nonlinearity

This note uses quadratic surface Lyapunov functions (SuLFs) to efficiently check if a double integrator in feedback with a saturation nonlinearity has L -gain less than > 0. We show that for many such systems, theL -gain is nonconservative in the sense that this is approximately equal to the lower bound obtained by replacing the saturation with a constant gain of 1. These results allow the use ...